Ultrasonic surgical blades

ABSTRACT

An ultrasonic surgical instrument including a waveguide extending along a longitudinal axis and an ultrasonic blade is disclosed. The ultrasonic blade includes a proximal end coupled to the waveguide, a distal end movable relative to the longitudinal axis in accordance with ultrasonic vibrations applied to the waveguide, an outer surface, a first layer adhered to at least a portion of the outer surface, and a second layer overlapping at least a portion of the first layer. At least a portion of the second layer contacts the outer surface.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional application claiming priority under 35U.S.C. § 121 to U.S. patent application Ser. No. 12/274,884, entitledULTRASONIC SURGICAL BLADES, filed Nov. 20, 2008, which issued on Jul. 3,2018 as U.S. Pat. No. 10,010,339, which claims the benefit under U.S.C.§ 119(e) to U.S. Provisional Patent Application Ser. No. 61/004,961,entitled ULTRASONIC SURGICAL BLADES, filed Nov. 30, 2007, the entiredisclosures of which are hereby incorporated by reference herein.

BACKGROUND

The present disclosure is generally directed to ultrasonic surgicalblades employed in ultrasonic instruments. At present, ultrasonicinstruments are used in open as well as minimally invasive surgicalprocedures, including endoscopic and laparoscopic surgical procedureswhere an end-effector portion of the ultrasonic instrument is passedthrough a trocar to reach the surgical site. Due, in part, to the risingpopularity of minimally invasive surgical procedures, ultrasonicinstruments are increasingly being used for the safe and effectivetreatment of many medical conditions. The operation of instrumentsemploying an ultrasonic transducer in this context is well known in theart and it will not be repeated herein for the sake of conciseness andbrevity. Stated briefly, an ultrasonic transducer excited by anelectrical generator produces mechanical vibrations at ultrasonicfrequencies, which are transmitted longitudinally through a transmissioncomponent or waveguide to an end-effector. The mechanical vibrationsinduce longitudinal, transverse, or torsional vibratory movement to theend-effector relative to the transmission component. The vibratorymovement of the end-effector generates localized heat within adjacenttissue, facilitating both cutting and coagulating of tissue at the sametime. Accordingly, the ultrasonic vibrations, when transmitted toorganic tissue at suitable energy levels using a suitable end-effector,may be used to cut, dissect, separate, lift, transect, elevate,coagulate or cauterize tissue, or to separate or scrape muscle tissueaway from bone with or without the assistance of a clamping assembly.

It is generally accepted that ultrasonic instruments, and particularlyultrasonic instruments comprising contact ultrasonic elements, providecertain advantages over other surgical instruments. Among theseadvantages is that the ultrasonic mechanical vibrations can cut andcoagulate tissue at the same time using relatively lower temperaturesthan conventional cutting and cauterizing surgical instruments. Thenature of ultrasonic instruments lend themselves to multipleapplications and a variety of end-effectors may be designed to performnumerous functions.

Ultrasonic instruments may be classified into single-elementend-effector devices and multiple-element end-effector devices.Single-element end-effector devices include instruments such as blades,scalpels, hooks, and/or ball coagulators. Although generally, thesetypes of end-effectors are formed of solid materials suitable forpropagating ultrasonic waves, there also exist end-effectors with ahollow core to deliver a fluid stream or provide a suction channel.Multiple-element end-effectors include the single-elementend-effector—blade—operatively coupled to a clamping mechanism forpressing or clamping tissue between the blade and the clampingmechanism. Multiple-element end-effectors include clamping scalpels,clamping coagulators or any combination of a clamping mechanism and asingle-element end-effector. Clamping end-effectors are particularlyuseful when a substantial amount of pressure is necessary to effectivelycouple ultrasonic energy from the blade to the tissue. Clampingend-effectors apply a compressive or biasing force to the tissue topromote faster cutting and coagulation of tissue, particularly loose andunsupported tissue.

With this general background in mind, it should be noted that surgicalenvironments where ultrasonic instruments are employed can beparticularly harsh due to the mechanical vibratory forces applied to theend-effector, the resulting thermal effects, and the general causticconditions present at the surgical site. For example, in use, theend-effector comes into contact with surgical matter, which includescoagulants, proteins, blood, tissue particles, and other constituentfluids. Over time, the surgical matter tends to desiccate and adhere tothe outer (e.g., external) surface of the end-effector. This buildup ofsurgical matter tends to reduce the performance of the end-effector byreducing the ability of the end-effector to cut and/or coagulate tissueand increasing the impedance at the end-effector/tissue interface. Tocompensate for the increase in interface impedance, the generatorsupplies increasing amounts of power to the end-effector to continuetransecting tissue until the power delivered by the generator exceeds apredetermined threshold at which time the generator shuts down or goesinto “lockout.” Lockout is a condition where the impedance of theend-effector is so high that the generator is unable to providemeaningful amounts of power to the tissue. Generator lockout is anundesirable result that occurs when the generator is unable to supplyadequate power to the end-effector to complete a transection under theincreased interface impedance condition. The completion of a transectionis indicated to the user by the visual separation of the tissue from thedevice end-effector. When the generator goes into lockout, the surgicalprocedure is interrupted. Therefore, generator lockout results inincreased cutting and transection times, or worse, down time during thesurgical procedure.

Accordingly, there is a need for an end-effector with a suitable coatingor suitable combination of a coating and a surface treatment to protectthe end-effector from harsh surgical environments. In this regard, thesuitable coating or suitable combination of a coating and a surfacetreatment prevents or minimizes buildup of surgical matter on the outersurface of the end-effector, minimizes generator lockout, minimizespower draw, improves pad wear in clamping type end-effectors, andimproves the thermal characteristics of the end-effector. There is alsoneeded a process of applying one or more suitable coatings to an outersurface of an end-effector to enable the adhesion of the one or morecoatings to the outer surface of the end-effector.

SUMMARY

In one general aspect, the various embodiments are directed to anultrasonic surgical instrument including a waveguide extending along alongitudinal axis and an ultrasonic blade. The ultrasonic blade includesa proximal end coupled to the waveguide, a distal end movable relativeto the longitudinal axis in accordance with ultrasonic vibrationsapplied to the waveguide, an outer surface, a first layer adhered to atleast a portion of the outer surface, and a second layer overlapping atleast a portion of the first layer. At least a portion of the secondlayer contacts the outer surface.

FIGURES

The novel features of the various embodiments are set forth withparticularity in the appended claims. The various embodiments, however,both as to organization and methods of operation, may be best understoodby reference to the following description, taken in conjunction with theaccompanying drawings as follows.

FIG. 1 illustrates one embodiment of a multi-element end-effector.

FIG. 2 illustrates a cross-sectional view of an ultrasonic blade portionof the multi-element end-effector shown in FIG. 1 taken along line 2-2.

FIG. 3 illustrates one embodiment of a multi-element end-effector.

FIG. 4 illustrates a cross-sectional view of the ultrasonic bladeportion of the multi-element end-effector shown in FIG. 3 taken alongline 4-4.

FIG. 4A is an enlarged view of a portion of the cross-sectional portionof one embodiment of the ultrasonic blade portion of the multi-elementend-effector shown in FIG. 3.

FIG. 4B is an enlarged view of a portion of the cross-sectional portionof one embodiment of the ultrasonic blade portion of the multi-elementend-effector shown in FIG. 3.

FIG. 4C is an enlarged view of a portion of the cross-sectional portionof one embodiment of the ultrasonic blade portion of the multi-elementend-effector shown in FIG. 3.

FIG. 5 illustrates one embodiment of a multi-element end-effector.

FIG. 6 illustrates a cross-sectional view of the ultrasonic bladeportion of the multi-element end-effector shown in FIG. 5 taken alongline 6-6.

FIG. 7 illustrates one embodiment of a multi-element end-effector.

FIG. 8 illustrates a cross-sectional view of the ultrasonic bladeportion of the multi-element end-effector shown in FIG. 7 taken alongline 8-8.

FIG. 9 illustrates one embodiment of a multi-element end-effector.

FIG. 10 illustrates a cross-sectional view of the ultrasonic bladeportion of the multi-element end-effector shown in FIG. 9 taken alongline 10-10.

FIG. 11 illustrates one embodiment of a multi-element end-effector.

FIG. 12 illustrates a cross-sectional view of the ultrasonic bladeportion of the multi-element end-effector shown in FIG. 11 taken alongline 12-12.

FIG. 13 illustrates one embodiment of a single element end-effector.

FIG. 14 illustrates a cross-sectional view of an ultrasonic bladeportion of the single element end-effector shown in FIG. 13 taken alongline 14-14.

FIG. 15 illustrates one embodiment of a multi-element end-effector.

FIG. 16 illustrates a cross-sectional view of an ultrasonic bladeportion of the multi-element end-effector shown in FIG. 15 taken alongline 16-16.

FIG. 17 illustrates one embodiment of a multi-element end-effector.

FIG. 18 illustrates a cross-sectional view of an ultrasonic bladeportion of the multi-element end-effector shown in FIG. 17 taken alongline 18-18.

DESCRIPTION

Before explaining the various embodiments in detail, it should be notedthat the embodiments are not limited in application or use to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings and description. The surgical instruments andend-effector configurations disclosed herein are illustrative only andnot meant to limit the scope of the appended claims or applicationthereof. The illustrative embodiments may be implemented or incorporatedin other embodiments, variations and modifications, and may be practicedor carried out in various ways. Furthermore, unless otherwise indicated,the terms and expressions employed herein have been chosen for thepurpose of describing the illustrative embodiments for the convenienceof the reader and are not to limit the scope thereof.

The various embodiments relate, in general, to end-effectors for use inultrasonic surgical instruments. An ultrasonic surgical instrumentgenerally comprises an ultrasonic transducer, an ultrasonicallyactivated end-effector, and a substantially solid, or hollow, ultrasonicwaveguide that connects the ultrasonic transducer to the end-effector.The ultrasonic transducer is contained in a transducing handpiece. Theend-effector may be formed of a base material (e.g., body) that issuitable for efficiently transmitting or propagating acoustic waves atultrasonic frequencies. Thus, the end-effector is anultrasound-propagating element, which may be coupled to the ultrasonictransducer either directly or by way of the ultrasonic transmissionwaveguide. Examples of ultrasonic surgical instruments are disclosed inU.S. Pat. Nos. 5,322,055 and 5,954,736 and combinations of ultrasonicend-effectors (e.g., blades) and surgical instruments are disclosed inU.S. Pat. Nos. 6,309,400 B2, 6,278,218 B1, 6,283,981 B1, and 6,325,811B1, which are incorporated herein by reference in their entirety. Thesereferences provide a suitable general description of ultrasonicinstruments and end-effectors. Accordingly, the particular operation ofsuch ultrasonic instruments and end-effectors will not be discussed indetail herein.

More particularly, the embodiments are directed to ultrasonicend-effectors comprising one or more coatings formed as layers ofmaterials, surface treatments, and/or any combination thereof. Asuitable coating formed on an outer surface of an ultrasonicend-effector provides a lubricating effect and, therefore, is useful inminimizing adhesion of surgical matter to the outer surface of theend-effector. The lubricating coating also reduces friction between theend-effector and the tissue and thus minimizes the interface impedancebetween the end-effector and the tissue and reduced the heat buildup inthe end-effector. This results in less power being drawn from theultrasonic generator and an end-effector with a cooler thermal profilethat minimizes generator lockout and improves the overall operationalstability of the surgical instrument. One skilled in the art wouldexpect that a decrease in average power draw (due, again, to reducedinterface impedance) would result in a corresponding increase in thetime required to perform surgical procedures such as the cutting andcoagulation of a tissue bundle. However, this tradeoff in transectiontime has not been seen in testing and, in fact, an unexpected decreasein transection times has been consistently obtained. Furtherinvestigation has revealed two causes for the unexpected results thatheretofore have not been described in the art: (1) the lower coefficientof friction coatings (most coatings presented herein have low frictionconstituents such as polytetrafluoroethylene generally known as TEFLON®and referred to herein below as PTFE) do not adhere to tissue and thusthe tissue releases from the blade (the indication of a completedtransection) more uniformly and more quickly than a comparable uncoatedblade and (2) the lower coefficient of friction and, therefore,interface impedance, results in a lower average power draw and thereforefar fewer incidents of generator lockout. In some embodiments, thetransection time has been reduced by about 34% by virtue of the firstlisted cause. In some embodiments, lengths of thick, tough tissue(uterine broad ligament, for example) have been transected in successiveapplications with a coated end-effector blade while a comparableuncoated instrument was unable (in any reasonable length of time) toaccomplish the same task; this due to the second listed cause. In use,various embodiments of the end-effector blades comprising one or morecoatings as described herein, may improve tissue effects such ashemostasis by providing more uniform transection and/or coagulation oftissue.

As described herein, a coating may comprise one or more layers ofmaterials formed on an outer surface of a body portion of an ultrasonicend-effector. The outer surface of the end-effector may be partially orcompletely coated with one or more than one layer of material. Eachlayer may comprise one or more materials. In other embodiments, one ormore surface treatments may be applied either to the entire end-effectorbody or to a portion thereof. Still in other embodiments, theend-effector body may comprise a combination of coatings andapplications of surface treatments. This combination may be applied tothe entire end-effector or to a portion thereof.

In some embodiments, materials, surface treatments, and/or combinationsthereof, may be suitably applied to an outer surface of theend-effector, or portion thereof, to produce an end-effector having acoefficient of friction that is lower than that of the end-effector basematerial alone. End-effectors with a lower coefficient of frictionoperate at lower temperatures and minimize generator lockout promotingfaster cutting of tissue. In other embodiments, surface treatments maybe suitably applied to an outer surface of the end-effector, or portionthereof, to produce an end-effector having a coefficient of frictionthat is greater than that of the end-effector base material alone. Endeffectors with a higher coefficient of friction improve the tissuesealing effects of the end-effector. Therefore, in some embodiments, itmay be desirable to provide an end-effector with a lower coefficient offriction in the cutting region and a higher coefficient of friction inthe tissue sealing region by applying various combinations of coatingsand surface treatments to different portions of the end-effector.

Certain embodiments will now be described to provide an overallunderstanding of the principles of the structure, function, manufacture,and use of the devices and methods disclosed herein. One or moreexamples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting embodiments and the scope of thevarious embodiments is defined solely by the claims. The featuresillustrated or described in connection with one embodiment may becombined with the features of other embodiments. Such modifications andvariations are intended to be included within the scope of the appendedclaims.

It will be appreciated that the terms “proximal” and “distal” are usedherein with reference to a clinician gripping a hand piece assembly ofan ultrasonic surgical instrument. Thus, the end-effector is distal withrespect to the more proximal hand piece assembly. It will be furtherappreciated that, for convenience and clarity, spatial terms such as“top” and “bottom” also are used herein with respect to the cliniciangripping the hand piece assembly. However, surgical instruments are usedin many orientations and positions, and these terms are not intended tobe limiting and absolute.

FIG. 1 illustrates one embodiment of a multi-element end-effector 100.In the illustrated embodiment, the multi-element end-effector 100comprises a clamp arm assembly 102, shown in an open position,operatively coupled to an ultrasonic surgical blade 112 (blade). Themultiple-element end-effector 100 may be employed in a conventionalclamping coagulating type ultrasonic instrument, for example. The clamparm assembly 102 comprises a clamp arm 104 and a tissue pad 106 attachedto the clamp arm 104. The blade 112 is an ultrasound-propagating elementsuitable for coupling to conventional ultrasonic surgical instruments.The blade 112 comprises a body 108 having a proximal end and a distalend and defining an elongated treatment region therebetween. The body108 defines a longitudinal axis A extending between the proximal end andthe distal end. The proximal end is adapted and configured to couple toan ultrasonic transducer either directly or through an ultrasonictransmission waveguide in a known manner. Mechanical vibrations producedby the ultrasonic transducer propagate along the transmission waveguideand are coupled to the proximal end of the body 108. The distal end ofthe body 108 is selected such that it is movable relative to thelongitudinal axis A by the mechanical vibrations produced by theultrasonic transducer. The distal end and the elongated treatment regionis used to effect tissue (e.g., dissect, transect, cut, coagulate).These tissue effects may be enhanced by clamping the tissue between thecamp arm 104 and the blade 112.

In one embodiment, a coating 116 may be formed or applied on at least aportion of an outer (e.g., external) surface of the body 108 that atleast corresponds with the elongated treatment region. The coating 116may comprise one or more than one layer 110 formed on the outer surfaceof the body 108. Each of the one or more than one layer 110 may consistof one or more than one material. Accordingly, in one embodiment, thelayer 110 may in effect comprise several sub-layers. In one embodiment,the coating 116 may consist of a base layer (e.g., primer layer, firstlayer) as well as an overcoat layer (e.g., top layer, second layer) andone or more than one layer 110 therebetween. The surface area of thebody 108 may include a surface treatment applied thereto to enhance theadhesion of the layer 110 of material to the body 108. The coated blade112 enhances tissue effects during dissecting, transecting, cutting, andcoagulating and improves the operational stability of the ultrasonicsurgical instrument by minimizing or eliminating generator lockout.

FIG. 2 illustrates a cross-sectional view of the ultrasonic surgicalblade 112 portion of the multi-element end-effector 100 taken along line2-2 in FIG. 1. As shown in the cross-sectional view of FIG. 2 of theillustrated embodiment, the body 108 has a substantially circular crosssectional shape. In other embodiments, the body 108 may have anysuitable cross sectional shape and may be symmetric or asymmetric innature. For example, the body 108 may have a cross-sectional shape thatdefines a triangle, square, rectangle, pentagon, hexagon, any suitablepolygon, or irregular shape, whether symmetric or asymmetric. The body108 may be fabricated from a base material suitable for transmission ofultrasonic energy in the form of acoustic waves. The base material ofthe body 108 may comprise titanium (e.g., Ti6Al-4V ELI), aluminum,stainless steel, or any material or composition that is suitable forpropagating acoustic waves efficiently, for example.

In one embodiment, the coating 116 may be formed as one layer 110 overat least a portion of the outer surface of the blade body 108. The layer110 may consist of at least one material and in other embodiments mayinclude multiple layers consisting of a base material (e.g., primerlayer, first layer) and an overcoat material (e.g., top layer, secondlayer) as described in more detail herein with reference to FIGS. 3 and4. The thickness of the layer 110 may be anywhere from about 0.0001 toabout 0.010 inches (0.1 mils to 10 mils). The coating 116 may partiallyor completely cover the outer surface of the body 108. The layer 110 maybe formed over the entire body 108 or may be formed over portions of thebody 108. The coating 116 material may be selected to have a lowercoefficient of friction than the body 108 material.

The layer 110 may comprise a variety of materials including polymericand polymer containing materials. The term “polymeric materials” and theword polymer, as used herein, include, but are not limited to,homopolymers, copolymers, terpolymers, and the like. Non-limitingexamples of polymeric and polymer-containing materials includetetrafluoroethylene (TFE) and hexafluoropropylene (HFP) copolymers(FEP), liquid FEP, FEP/ceramic composites, liquid FEP ceramic epoxycomposites, polytetrafluoroethylene (PTFE or TEFLON®), and PTFE/ceramiccomposites. In other non-limiting embodiments, the layer 110 maycomprise a dry film lubricant, such as, but not limited to, tungstendisulfide, molybdenum disulfide, graphite, and fluorinated polymers.Still in other non-limiting embodiments, the layer 110 may compriseceramics, such as, but not limited to, metal oxydes, metal nitrides, andmetal carbides. Examples of ceramics, include, but are not limited to,chromium carbide, tungsten carbide, titanium nitride, alumina, andchromium nitride. Yet in other non-limiting embodiments, the layer 110may comprise metals. Metals include, but are not limited to, aluminum,stainless steel, and molybdenum. In other non-limiting embodiments, thelayer 110 may comprise a metallized ceramic, such as, but not limitedto, stainless steel embedded in ceramic.

In various embodiments, the coating 116 may be formed in multiple layersincluding any of the materials previously discussed with respect to thelayer 110. Examples of multi-layer coatings or composites include, butare not limited to, molybdenum/alumina/tungsten carbide, aluminumoxide/stainless steel, aluminum oxide/stainless steel 15/15%, chromiumcarbide/tungsten oxide, molybdenum/aluminum oxide/tungsten carbide,cobalt/molybdenum, graphite/tungsten oxide, aluminum oxide/stainlesssteel 25/30%, molybdenum/aluminum oxide/tungsten carbide/stainlesssteel, or chromium carbide/tungsten oxide, among other suitablematerials.

In use, the blade 112 may be exposed to particularly harsh environmentsincluding ultrasonic vibrations, heat, and caustic solutions of bloodand proteins referenced to herein as surgical matter. Consequently, theharsh operating environment tends to delaminate, erode, or wear thecoating 116. Accordingly, the layer 110 should be applied to the body108 using any suitable application technique that promotes good adhesionbetween the base material of the body 108 and the layer 110 to preventor minimize delamination, erosion, or wear of the layer 110 from thebody 108. The layer 110 may be applied to the body using suitablematerial application techniques: coating, dipping, spraying, brushing,drying, melting, laser curing, anodizing, electroplating, electrolesschemical deposition, sintering, fused curing, physical vapor deposition(PVC), chemical vapor deposition (CVD), thermal spray, thick film highvelocity oxygen fuel (HVOF) plasma, and any other suitable materialapplication techniques. Other well known material deposition techniquesare described in U.S. Pat. Nos. 7,041,088 and 6,663,941, which areincorporated herein by reference. One suitable material applicationtechnique is a process developed by Integrated Surgical Sciences, Corp.(ISSC) of Sedalia, Colo., USA. Alternatively, the materials for formingthe coating 116, or any constituent material forming the various layersthereof, may be purchased from ISSC and applied in accordance with anysuitable material application techniques.

In various embodiments, a surface treatment or a plurality of surfacetreatments may be applied to the body 108 using a variety of techniques:peening, sand blasting, micro blasting, bead blasting, knurling,engraving, chemical treatment such as acid or base etching, laseretching, plasma etching, corona discharge etching, heat etching,carving, scoring, vibratory deburring, abrasive flow machining, andother techniques. The surface treatment can advantageously improve theadhesion of the layer 110 to the surface of the body 108. However, careshould be taken when applying surface treatments to prevent damage tothe body 108 during application, which later may lead to failure of theblade 112 during use. For example, surface bead blasting may increasethe stress concentrations in the end-effector body 108 and may lead tothe failure of the end-effector during use. FIG. 4A illustrates oneexample of a surface treatment 108A that may be applied to the surfaceof the body 108 to enhance the adhesion of the layer 110 to the surfaceof the body 108.

In use, the blade 112 comprising the coating 116 formed over the body108 provides several advantages such as improved cutting and coagulatingfunctions over an uncoated blade. In one embodiment, the coating 116 hasa coefficient of friction that is lower than the coefficient of frictionof the surface of the base material of the body 108 alone. Thus, thecoating 116 forms a lubricious layer over at least a portion of the body108. The blade 112 comprising the lubricious coating 116 providesseveral benefits and/or advantages over conventional uncoated bareend-effector blades. For example, the coated blade 112 provides improvedtissue cutting (e.g., transecting) along the longitudinal length of theblade 112 resulting in more uniform transection of tissue, improvedvessel sealing and homogeneity of the tissue layer, and improved thermaland structural properties of the blade 112, which facilitates moreuniform transection of the tissue. The coated blade 112 may furtherfacilitate uniform serosa-to-serosa adhesion along the cut length of thetissue, thus minimizing or eliminating discontinuities of adhesion alongthe tissue cut length, which commonly occur with conventional uncoatedblades. The lubricious property of the coating 116 also minimizes theadhesion of surgical matter to the surface of the blade 112 duringsurgical procedures. As previously discussed, “surgical matter” includescoagulants, proteins, blood, tissue, and/or other constituent fluids,which may be present during a surgical procedure and tend to desiccateand adhere to the surface of uncoated blades raising the interfaceimpedance of the blade. As previously discussed, to compensate for theincreased impedance, the ultrasonic generator supplies increasingamounts of power to the blade to continue transecting tissue until thepower delivered by the generator exceeds a predetermined threshold atwhich time the generator shuts down or goes into “lockout.” Aspreviously discussed, lockout is a condition where the impedance of theend-effector is so high that the generator is unable to providemeaningful amounts of the power to the tissue. Therefore, by minimizingthe deposition, buildup, or adhesion of surgical matter, the coatedblade 112 reduces the electrical power required to operate the blade 112when transecting tissue. As a result, the coated blade 112 minimizes thepower supplied by the generator and minimizes or prevents lockouts ofthe generator.

Those skilled in the art will appreciate that ultrasonic end-effectorblades are relatively efficient and that the electrical power requiredfor driving the end-effector blade correlates well with the powerdelivered to tissue loads. Essentially, the lubricious coating 116reduces the friction between the blade 112 and the tissue, thus reducingthe thermal profile of the blade 112. Because the tissue does not adhereto the coating 116, it releases from the blade 112 more easily anduniformly than an uncoated blade requiring less average power draw (lesstotal energy applied) and less time (even less total energy applied)than an uncoated blade giving a truly unexpected and synergistic effect.In certain instances, the time required to transect tissue, for example,may be reduced by as much as 34%. Additionally, because the coated blade112 reduces or minimizes the number of generator lockouts that may occurover a surgical procedure, the coated blade 112 even more substantiallyreduces the overall time required to complete the surgical procedure.

It is generally well known that tissue pads tend to degrade and wearover time due to frictional engagement with a blade when no tissue ispresent therebetween. The lubricious coating 116, however, also lowersthe coefficient of friction between the coated blade 112 and the tissuepad 106 and as a result can extend the life of the tissue pad 106.Accordingly, the coated blade 112 can reduce or minimize the degradationand deterioration of the tissue pad 106 caused by abrasion andfrictional engagement with the blade 112. Consequently, the coated blade112 can substantially extend the operational life of the tissue pad 106when compared to conventional uncoated blades.

FIG. 3 illustrates one embodiment of a multi-element end-effector 200.In the illustrated embodiment, the multi-element end-effector 200comprises a clamp arm assembly 202, shown in an open position,operatively coupled to an ultrasonic surgical blade 212 (blade). Themultiple-element end-effector 200 may be employed in clampingcoagulating type ultrasonic instruments, for example. The clamp armassembly 202 comprises a clamp arm 104 and a tissue pad 106 attachedthereto. The blade 212 is an ultrasound-propagating element suitable foruse in ultrasonic surgical instruments. The body 108, previouslydiscussed with reference to FIGS. 1 and 2, forms a portion of the blade212. As previously discussed, the body 108 comprises a proximal end anda distal end and defines an elongated treatment region therebetween. Theproximal end is adapted and configured to couple to an ultrasonictransducer either directly or through an ultrasonic transmissionwaveguide. The distal end and the treatment region is used to effecttissue (e.g., dissect, transect, cut, coagulate). In one embodiment, acoating 216 is formed on at least a portion of the outer surface of thebody 108 that at least corresponds with the elongated treatment region.The coating 216 may comprise at least two layers 210, 214 of materials.In the illustrated embodiment, a primer layer 214 (e.g., base layer,first layer) may be formed on the outer surface of the body 108. Anovercoat layer 210 (e.g., top layer, second layer) may be formed overthe primer layer 214. In one embodiment, the overcoat layer 210 may beformed over a portion of the primer layer 214. The primer layer 214forms a suitable adhesive bond with the outer surface of the body 108and is formulated to enhance the adhesion of the overcoat layer 210 tothe body 108. The primer layer 214 and/or the overcoat layer 210 eachmay comprise multiple layers of materials. The layers 210, 214 may beformed on the body 108 using any suitable material application techniqueincluding techniques discussed herein with respect to FIGS. 1 and 2(e.g., the coating application process developed by ISSC).

FIG. 4 illustrates a cross-sectional view of the ultrasonic surgicalblade 212 portion of the multi-element end-effector 200 taken along line4-4 in FIG. 3. As shown in the cross-sectional view of FIG. 4, in theillustrated embodiment, the coating 216 comprises multiple layers 214,210 of materials. The primer layer 214 is the first layer applied to thebody 108. In various embodiments, the primer layer 214 may comprise apolymer or polymeric materials and/or ceramic. In various embodiments,the primer layer 214 may comprise FEP or liquid FEP. In one embodiment,the primer layer 214 may comprise aluminum oxide or any suitablematerial composition containing aluminum oxide. In another embodimentthe primer layer 214 may comprise titanium nitride or any suitablematerial composition containing titanium nitride. The overcoat layer 210is then applied over the primer layer 214 material to form the top layerof the coating 216, which has lubricious properties similar to thecoating 116 previously discussed with reference to FIGS. 1 and 2. Theovercoat layer 210 may be applied to a portion of the primer layer 214or may be applied over the entire primer layer 214. The overcoat layer210 may comprise a variety of materials including polymeric and polymercontaining materials. As previously discussed, the term “polymericmaterials” and the word polymer, as used herein, include, but are notlimited to, homopolymers, copolymers, terpolymers, and the like. Aspreviously discussed, non-limiting examples of polymeric andpolymer-containing materials include FEP, liquid FEP, FEP/ceramiccomposites, liquid FEP ceramic epoxy composites, PTFE, and PTFE/ceramiccomposites. In other non-limiting embodiments, the overcoat layer 210may comprise a dry film lubricant, such as, but not limited to, tungstendisulfide, molybdenum disulfide, graphite, and fluorinated polymers.Still in other non-limiting embodiments, the overcoat layer 210 maycomprise ceramics, such as, but not limited to, metal oxydes, metalnitrides, and metal carbides. Examples of ceramics, include, but are notlimited to, chromium carbide, tungsten carbide, titanium nitride,alumina, and chromium nitride. Yet in other non-limiting embodiments,the overcoat layer 210 may comprise metals. Metals include, but are notlimited to, aluminum, stainless steel, and molybdenum. In othernon-limiting embodiments, the overcoat layer 210 may comprise ametallized ceramic, such as, but not limited to, stainless steelembedded in ceramic. In one embodiment, the overcoat layer 210 may beapplied using conventional powder coating techniques.

FIG. 4A is an enlarged view of the cross-sectional portion of oneembodiment of the blade 216 shown in FIG. 4. As shown in FIG. 4A, in oneembodiment, the surface of the body 108 may be prepared with a suitablesurface treatment 108A prior to the application of the primer layer 214to further enhance or promote the adhesion of the primer layer 214material to the outer surface of the body 108. In another embodiment, asurface treatment may be applied to the surface of the primer layer 214prior to the application of the overcoat layer 210 to enhance theadhesion of the overcoat layer 210 to the primer layer 214. The surfacetreatment 108A may be applied the surface of the body 108 using any ofthe techniques previously described with reference to FIGS. 1 and 2(e.g., peening, micro blasting, sand blasting, bead blasting, knurling,engraving, chemical treatment such as acid or base etching, laseretching, plasma etching, corona discharge etching, heat etching,carving, scoring, and other techniques) to produce a predeterminedsurface roughness R_(A) of about 16 microinches (μin) to about 256 μin.In one embodiment, a surface treatment may be applied to an outersurface of the body 108 to produce a predetermined surface roughnessR_(A) of about 16 μin to about 63 μin, for example. However, othersurface roughnesses also may be produced. After coating the body 108with the primer layer 214, the preferred surface roughness R_(A) rangeof the finished product is about 16 μin to about 32 μin.

FIG. 4B is an enlarged view of the cross-sectional portion of oneembodiment of the blade 216 shown in FIG. 4. As shown in FIG. 4B, in oneembodiment, a primer layer 218 may be formed directly on the outersurface of the body 108. In one embodiment, the primer layer 218 has asurface 220 having a predetermined surface roughness that enhances orpromotes adhesion of the topcoat layer 210 to the primer layer 218. Inone embodiment, the surface 220 may be achieved using a rough titaniumnitride coating as the primer layer 218. The rough surface 220 of theprimer layer 218 provides a good bonding surface for a topcoat layer 210having a low coefficient of friction. The primer layer 218 comprisingtitanium nitride provides a good bond to the outer surface of the body108 without the need for a surface treatment. In another embodiment, thesurface 220 may be achieved using a rough aluminum oxide coating as theprimer layer 218 to provide a good bonding surface for a topcoat layer210 having a low coefficient of friction. The aluminum oxide coatingalso may provide a good bond to the outer surface of the body 108without the need for a surface treatment.

FIG. 4C is an enlarged view of the cross-sectional portion of oneembodiment of the blade 216 shown in FIG. 4. As shown in FIG. 4C, in oneembodiment, a primer layer 222 may be formed directly on the outersurface of the body 108. In one embodiment, the primer layer 222 has asurface that enhances or promotes adhesion of the topcoat layer 210 tothe primer layer 222.

In various embodiments, any of the primer layers 214, 218, 222 maycomprise aluminum oxide, titanium nitride, FEP, or liquid FEP, whichpassivates the surface of the body 108 for better adhesion of theovercoat layer 210. In various embodiments, any of the primer layers214, 218, 222 may consist essentially of aluminum oxide, titaniumnitride, FEP or liquid FEP. In other embodiments, any of the primerlayers 214, 218, 222 may comprise any of the base materials previouslydiscussed with reference to FIGS. 2-4.

FIG. 5 illustrates one embodiment of a multi-element end-effector 300.In the illustrated embodiment, the multi-element end-effector 300comprises a clamp arm assembly 302, shown in an open position,operatively coupled to an ultrasonic surgical blade 312 (blade). Themultiple-element end-effector 300 may be employed in clampingcoagulating type ultrasonic instruments, for example. The clamp armassembly 302 comprises a clamp arm 104 and a tissue pad 106 attachedthereto. The blade 312 is an ultrasound-propagating element suitable foruse in ultrasonic surgical instruments. The body 108, previouslydiscussed with reference to FIGS. 1-4, forms a portion of the blade 312.As previously discussed, the body 108 comprises a proximal end and adistal end and defines an elongated treatment region therebetween. Theproximal end is adapted and configured to couple to an ultrasonictransducer either directly or through an ultrasonic transmissionwaveguide. The distal end and the elongated treatment region is used toeffect tissue (e.g., dissect, transect, cut, coagulate). A surfacetreatment 310 may be applied to an outer surface of the body 108 that atleast corresponds with the elongated treatment region. Those skilled inthe art will appreciate, that the surface treatment 310 having aparticular surface roughness R_(A) may be produced using the well knowntechniques previously described with reference to FIG. 2, for example,provided that the underlying structure of the body 108 is notcompromised.

FIG. 6 illustrates a cross-sectional view of the ultrasonic blade 312portion of the multi-element end-effector 300 taken along line 6-6 inFIG. 5. With reference to FIGS. 5 and 6, in one embodiment, the surfacetreatment 310 (e.g., roughness) may be formed or applied to the outersurface of the body 108 or may be formed on the outer surface of acoating layer applied to the body 108 as described later herein withreference to FIGS. 7 and 8. A suitable surface treatment 310 has acoefficient of friction that is greater than the coefficient of frictionof the untreated outer surface area of the body 108. A rough“frictional” surface treatment 310 has a predetermined surface roughnessR_(A) of about 16 μin to about 256 μin. In one embodiment, the rough“frictional” surface treatment 310 has a predetermined surface roughnessR_(A) of about 32 μin. The surface treatment 310 may be formed on theouter surface of the body 108 to assist the blade 312 to frictionallyengage (grip) and stabilize the walls of blood vessels and as a resultprovide improved and more reliable vessel sealing. Because of therougher surface treatment 310, the blade 312 remains engaged with thetissue long enough to prevent the vessel walls from pulling away fromthe seal line. Consequently, this promotes the communication of tissuecollagen from one side of the seal line to the other to create a veryreliable seal, as will be appreciated by those skilled in the art.

FIG. 7 illustrates one embodiment of a multi-element end-effector 400.In the illustrated embodiment, the multi-element end-effector 400comprises a clamp arm assembly 402, shown in an open position,operatively coupled to an ultrasonic surgical blade 412 (blade). Themultiple-element end-effector 400 may be employed in a clampingcoagulating ultrasonic instrument, for example. The clamp arm assembly402 comprises a clamp arm 104 and a tissue pad 106 attached thereto. Theblade 412 is an ultrasound-propagating element suitable for use inultrasonic surgical instruments. The body 108, as previously discussedwith reference to FIGS. 1-6, forms a portion of the blade 412. Aspreviously discussed, the body 108 comprises a proximal end and a distalend and defines an elongated treatment region therebetween. The proximalend is adapted and configured to couple to an ultrasonic transducereither directly or through an ultrasonic transmission waveguide. Thedistal end and the treatment region are used to effect tissue (e.g.,dissect, transect, cut, coagulate). In one embodiment, a coating 416comprising a first layer 410 of material may be formed on an outersurface of the body 108 using any of the material application techniquespreviously described (e.g., the coating application process developed byISSC). The first layer 410 may comprise any of the polymeric materials,dry film lubricants, ceramics, metals, and metallized ceramicspreviously described with reference to FIG. 2.

FIG. 8 illustrates a cross-sectional view of the ultrasonic blade 412portion of the multi-element end-effector 400 taken along line 8-8 inFIG. 7. A surface treatment 414 having a predetermined roughness R_(A)of about 16 μin to about 256 μin may be produced over the layer 410using any of the techniques previously discussed with reference to FIG.2. The body 108 defines a longitudinal axis A extending between theproximal end and the distal end. The distal end of the body 108 ismovable relative to the longitudinal axis A by the vibrations producedby the transducer propagating along the longitudinal axis A. Withreference to FIGS. 7 and 8, in one embodiment, the surface treatment 414having a predetermined surface roughness R_(A) of about 16 μin to about256 μin may be formed over the first layer 410, or portions thereof.However, other suitable values surface roughness R_(A) may besuccessfully produced. For example, a surface treatment of apredetermined surface roughness R_(A) having a coefficient of frictionthat is greater than the coefficient of friction of the first layer 410may be produced over the first layer 410 to assist the blade 412 ingripping and stabilizing the walls of blood vessels and producingbetter, more reliable, vessel seals. The surface treatment 414, having acoefficient of friction slightly greater than the first layer 410,enables the blade 412 to remain engaged with the tissue long enough toprevent the joined vessels walls from pulling away or shrinking awayfrom the seal line prior to completing the sealing operation. It will beappreciated, that the surface treatment 414 may be formed over a portionof the body 108 in order to take advantage of the lubricious propertiesof the coating 410 for cutting operations while also taking advantage ofthe rougher surface treatment 414 portion for sealing operations.

FIG. 9 illustrates one embodiment of a multi-element end-effector 500.In the illustrated embodiment, the multi-element end-effector 500comprises a clamp arm assembly 502, shown in an open position,operatively coupled to an ultrasonic surgical blade 512 (blade). Themultiple-element end-effector 500 may be employed in clampingcoagulating type ultrasonic instruments, for example. The clamp armassembly 502 comprises a clamp arm 104 and a tissue pad 106 attachedthereto. The blade 512 is an ultrasound-propagating element suitable foruse in ultrasonic surgical instruments. The body 108, as previouslydiscussed with reference to FIGS. 1-8 forms a portion of the blade 512.As previously discussed, the body 108 comprises a proximal end and adistal end and defines an elongated treatment region therebetween. Theproximal end is adapted and configured to couple to an ultrasonictransducer either directly or through an ultrasonic transmissionwaveguide. The distal end and the treatment region are used to effecttissue (e.g., dissect, transect, cut, coagulate).

FIG. 10 illustrates a cross-sectional view of the ultrasonic blade 512portion of the multi-element end-effector 500 taken along line 10-10 inFIG. 9. A coating 516 comprising a layer 510 of material may be formedon at least a portion of an outer surface of the blade body 108. One ormore than one layer 510 of material may be formed on the body 108 usingany suitable application technique discussed herein (e.g., the coatingapplication process developed by ISSC).

With reference to FIGS. 9 and 10, in one embodiment, the one or morethan one layer 510 of material may be formed on the blade 512non-uniformly such that the layer 510 has variable thickness about theouter surface of the body 108. In the illustrated embodiment, the layer510 is formed thicker to assist thermal bonding. In one embodiment, athinner layer 510 a may be formed on a top surface portion of the body108 where the blade 516 comes in contact with the tissue pad 106 andthicker layers 510 b of the material may be formed on lateral surfaceportions of the body 108. A layer 510 c of any suitable thickness may beformed on the bottom surface portion of the body 108 opposite of the topsurface portion. In the illustrated embodiment, the layer 510 c on thebottom surface portion of the body 108 is formed with the same thicknessas the thinner layer 510 a. In other embodiments, the layer 510 c at thebottom surface portion of the body 108 may be formed with the samethickness as the thicker layers 510 b, thicker than the layers 510 b, orother suitable thicknesses. In other embodiments, multiple layers may beformed of varying thicknesses on the lateral portions of the body 108 toprevent excessive thermal damage to these areas of the seal. The one ormore than one layer 510 of material may comprise any of the polymericmaterials, dry film lubricants, ceramics, metals, and metallizedceramics previously discussed with reference to FIG. 2. In otherembodiments, a primer layer and/or a surface treatment may be applied tothe outer surface of the body 108 prior to the application of the one ormore than one layer 510 of material. To the extent that one embodimentof the blade 512 comprises a primer layer, the primer layer may compriseany of the base materials previously discussed with reference to FIGS. 2and 4. To the extent that one embodiment of the blade 512 comprises asurface treatment, the surface treatment may be applied in accordancewith the techniques previously discussed with reference to FIGS. 2 and4A.

FIG. 11 illustrates one embodiment of a multi-element end-effector 700.In the illustrated embodiment, the multi-element end-effector 700comprises a clamp arm assembly 702, shown in an open position,operatively coupled to an ultrasonic surgical blade 712 (blade). Themultiple-element end-effector 700 may be employed in clampingcoagulating type ultrasonic instruments, for example. The clamp armassembly 702 comprises a clamp arm 104 and a tissue pad 106 attachedthereto. The blade 712 is an ultrasound-propagating element suitable foruse in ultrasonic surgical instruments. The body 108, as previouslydiscussed with reference to FIGS. 1-10, forms a portion of the blade712. As previously discussed, the body 108 comprises a proximal end anda distal end defining an elongated treatment region. The proximal end isadapted and configured to couple to an ultrasonic transducer eitherdirectly or through an ultrasonic transmission waveguide. The distal endand the treatment region are used to effect tissue (e.g., dissect,transect, cut, coagulate).

FIG. 12 illustrates a cross-sectional view of the ultrasonic blade 712portion of the multi-element end-effector 700 taken along line 12-12 inFIG. 11. In various embodiments, a coating 716 may be formed on theouter surface of the blade body 108. The coating 716 may comprise one ormore layers of materials, surface treatments, and/or combinationsthereof. In the illustrated embodiment, a first layer 710 and a secondlayer 714 are formed on the outer surface of the body 108. In oneembodiment, the second layer 714 may be formed over a portion of thefirst layer 710. The one or more material layers 710, 714 may be formedon the body 108 using any suitable material application techniqueincluding techniques discussed herein (e.g., the coating applicationprocess developed by ISSC). As shown in FIG. 12, the blade 712 maycomprise multiple layers of materials, each of varying thicknesses. Thefirst layer 710 may be formed thicker on the lateral surface portions ofthe body 108 and may be formed thinner on the top surface portions ofthe body 108, for example, where the blade 712 contacts the tissue pad106. A second layer 714 may be formed on the first layer 710. The secondlayer 714 may be formed thicker on the top surface portion of the body108 where the blade 712 contacts the tissue pad 106 is relativelythinner on the lateral surface portions of the body 108. In one materialapplication technique, the first layer 710 is applied to the body 108and the second layer 714 is subsequently applied over on the first layer710 or, as shown in FIG. 12, over portions of the first layer 710. Thefirst and second layers 710, 714 may comprise any of the polymericmaterials, dry film lubricants, ceramics, metals, and metallizedceramics previously discussed with reference to FIGS. 2 and 4. In otherembodiments, a primer layer and/or a surface treatment may be applied tothe outer surface of the body 108 prior to the application of the firstand second layers 710, 714. To the extent that one embodiment of theblade 712 comprises a primer layer, the primer layer may comprise any ofthe base materials discussed with reference to FIGS. 2 and 4. To theextent that one embodiment of the blade 712 comprises a surfacetreatment, the surface treatment may be applied in accordance with thetechniques previously discussed with reference to FIGS. 2 and 4A.

FIG. 13 illustrates one embodiment of a single element end-effector 800.In one embodiment, the single element end-effector 800 comprises theultrasonic surgical blade 112 (blade), shown and described withreference to FIGS. 1 and 2. The single-element end-effector 800 may be ascalpel, hook, or ball coagulator, for example. As previously discussed,the coating 116 may be formed on at least a portion of an outer surfaceof the body 108. The coating 116 also may comprise one or more layers110 formed on the outer surface of the body 108.

FIG. 14 illustrates a cross-sectional view of the ultrasonic blade 112portion of the single element end-effector 800 taken along line 14-14 inFIG. 13. As shown in the cross-sectional view of FIG. 14, in theillustrated embodiment, the blade 112 and the body 108 may have asubstantially circular cross sectional shape. In other embodiments, theshape of the blade 112 may be selected according to the type ofend-effector used, such as any of the shapes described with reference toFIG. 2.

FIG. 15 illustrates one embodiment of a multi-element end-effector 900.In the illustrated embodiment, the multi-element end-effector 900comprises a clamp arm assembly 902, shown in an open position,operatively coupled to an ultrasonic surgical blade 912 (blade). Themultiple-element end-effector 900 may be employed in clampingcoagulating type ultrasonic instruments, for example. The clamp armassembly 902 comprises a clamp arm 104 and a tissue pad 106 attachedthereto. The blade 912 is an ultrasound-propagating element suitable foruse in ultrasonic surgical instruments. The body 108, as previouslydiscussed with reference to FIGS. 1-14, forms a portion of the blade912. As previously discussed, the body 108 comprises a proximal end anda distal end defining an elongated treatment region. The proximal end isadapted and configured to couple to an ultrasonic transducer eitherdirectly or through an ultrasonic transmission waveguide. The distal endand the treatment region are used to effect tissue (e.g., dissect,transect, cut, coagulate). A coating 916 may be formed on at least aportion of an outer surface of the body 108. The coating 916 also maycomprise one or more layers 910, 914 formed on the outer surface of thebody 108.

FIG. 16 illustrates a cross-sectional view of the ultrasonic blade 912portion of the multi-element end-effector 900 taken along line 16-16 inFIG. 15. In various embodiments, the coating 916 may be formed on aportion of the outer surface of the blade body 108. In one embodiment,the coating 916 may comprise a first layer 910 (e.g., primer layer,first layer) and a second layer 914 (e.g., topcoat layer, second layer).In one embodiment, the second layer 914 may be formed over a portion ofthe first layer 910. The first and second layers 910, 914 may compriseany of the polymeric materials, dry film lubricants, ceramics, metals,and metallized ceramics previously discussed with reference to FIGS. 2and 4. In other embodiments, a surface treatment may be applied to theouter surface of the body 108 prior to the application of the first andsecond layers 910, 914. To the extent that one embodiment of the blade912 comprises a surface treatment, the surface treatment may be appliedin accordance with the techniques previously discussed with reference toFIGS. 2 and 4A.

FIG. 17 illustrates one embodiment of a multi-element end-effector 1000.In the illustrated embodiment, the multi-element end-effector 1000comprises a clamp arm assembly 1002, shown in an open position,operatively coupled to an ultrasonic surgical blade 1012 (blade). Themultiple-element end-effector 1000 may be employed in clampingcoagulating type ultrasonic instruments, for example. The clamp armassembly 1002 comprises a clamp arm 104 and a tissue pad 106 attachedthereto. The blade 1012 is an ultrasound-propagating element suitablefor use in ultrasonic surgical instruments. The body 108, as previouslydiscussed with reference to FIGS. 1-16, forms a portion of the blade1012. As previously discussed, the body 108 comprises a proximal end anda distal end defining an elongated treatment region. The proximal end isadapted and configured to couple to an ultrasonic transducer eitherdirectly or through an ultrasonic transmission waveguide. The distal endand the treatment region are used to effect tissue (e.g., dissect,transect, cut, coagulate). A coating 1016 may be formed on at least aportion of an outer surface of the body 108. The coating 1016 also maycomprise one or more layers 1010, 1014 formed on the outer surface ofthe body 108.

FIG. 18 illustrates a cross-sectional view of the ultrasonic blade 1012portion of the multi-element end-effector 1000 taken along line 18-18 inFIG. 17. In various embodiments, a coating 1016 may be formed on adistal end of the outer surface of the blade body 108. The coating 1016may comprise a first layer 1010 (e.g., a primer layer, first layer) anda second layer 1014 (e.g., a topcoat layer, second layer) of material,surface treatment, and/or combination thereof. The first and secondlayers 1010, 1014 may comprise any of the polymeric materials, dry filmlubricants, ceramics, metals, and metallized ceramics previouslydiscussed with reference to FIGS. 2 and 4. In other embodiments, asurface treatment may be applied to the outer surface of the body 108prior to the application of the first and second layers 1010, 1014. Tothe extent that one embodiment of the blade 1012 comprises a surfacetreatment, the surface treatment may be applied in accordance with thetechniques previously discussed with reference to FIGS. 2 and 4A.

With reference now to FIGS. 1-18, in various embodiments, the blade 112(212, 312, 412, 512, 612, 712, 912, 1012) in addition to the showncircular cross sectional shape may have various cross sectional forms orshapes, which may be symmetrical or asymmetrical in nature. For example,the blade may comprise a square, rectangular, triangular, or otherpolygonal cross-sectional shapes. As previously discussed, in variousembodiments, the body 108 also may comprise a variety of symmetrical orasymmetrical shapes. For example, the body 108 may be curved in one ormore directions. More details regarding curved or asymmetric blades aredescribed in U.S. Pat. No. 6,283,981, which is incorporated herein byreference.

In still other embodiments, the body 108 may be configured with a neckor transition portion that protrudes from the proximal end of thetreatment region. The neck portion may be configured to attach to anultrasonic transmission waveguide by a stud, weld, glue, quick connect,or other suitable attachment methods, for example. In various otherembodiments, the body 108 and the ultrasonic transmission waveguide maybe formed as a single unitary body. In either configuration, theultrasonic transmission waveguide may have gain steps to amplify themechanical vibrations transmitted to the body 108 as is well known inthe art.

With reference to FIGS. 1-18, in one embodiment, any of theend-effectors described herein (e.g., blades 112, 212, 312, 412, 512,612, 712, 912, 1012) may comprise coatings formed of soft or deflectablelayers of material to establish frictional engagement (e.g., gripping)with the tissue for improved tissue sealing. Examples of deflectablematerials include materials having a durometer hardness of Shore D fromabout 25 to about 70 Shore units. In other embodiments, the end-effectormay include coatings formed of layers of material combined with othertechnologies such as augmentation via clips and other fasteners. Inother embodiments, the end-effector may include a lumen formed throughthe longitudinal axis A to facilitate suction and removal of expressedfluids from the sealing site to prevent excessive thermal damage to anon-value-added portion of the seal. In other embodiments, theend-effector may include a coating formed of one or more layers ofmaterials that are suitable for use on difficult/hard tissues such ascartilage and bone. In other embodiments, the end-effector may include asurface treatment that has a roughness R_(A) that is suitable for use ondifficult/hard tissues such as cartilage and bone.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present disclosure.

Any of the end-effectors described herein (e.g., blades 112, 212, 312,412, 512, 612, 712, 912, 1012) may be reconditioned for reuse after atleast one use. In one embodiment, reconditioning can include obtainingan ultrasonic surgical blade and applying at least one layer of a firstmaterial on at least a portion of the body 108 to form a lubriciouscoating on the outer surface of the body 108. The lubricious coating maybe applied in accordance with any suitable material applicationtechniques, including material application techniques described herein.Then, sterilizing the ultrasonic surgical blade and storing theultrasonic surgical blade in a sterile container. In another embodiment,reconditioning can include obtaining an ultrasonic surgical blade andforming at least one surface treatment on at least a portion of the body108 to produce a frictional coating on the outer surface of the body108. The surface treatment may be applied in accordance with anysuitable surface treatment techniques, including the surface treatmenttechniques described herein. Then, sterilizing the ultrasonic surgicalblade and storing the ultrasonic surgical blade in a sterile container.

Preferably, the various embodiments described herein will be processedbefore surgery. First, a new or used instrument is obtained and ifnecessary cleaned. The instrument can then be sterilized. In onesterilization technique, the instrument is placed in a closed and sealedcontainer, such as a plastic or TYVEK® bag. The container and instrumentare then placed in a field of radiation that can penetrate thecontainer, such as gamma radiation, x-rays, or high-energy electrons.The radiation kills bacteria on the instrument and in the container. Thesterilized instrument can then be stored in the sterile container. Thesealed container keeps the instrument sterile until it is opened in themedical facility.

It is preferred that the device is sterilized. This can be done by anynumber of ways known to those skilled in the art including beta or gammaradiation, ethylene oxide, steam. Accordingly, in one embodiment, anultrasonic surgical blade comprising a body having a proximal end, adistal end, and an outer surface, the distal end is movable relative toa longitudinal axis in accordance with ultrasonic vibrations applied tothe proximal end, and a lubricious coating being formed on at least aportion of the outer surface of the body, is obtained. The ultrasonicsurgical blade is then sterilized and stored in a sterile container. Inanother embodiment, an ultrasonic surgical blade comprising a bodyhaving a proximal end, a distal end, and an outer surface, the distalend is movable relative to a longitudinal axis by ultrasonic vibrationsapplied to the proximal end and a predetermined surface treatment havinga predetermined surface roughness being formed on at least a portion ofthe body, is obtained. The ultrasonic surgical blade is then sterilizedand stored in a sterile container.

Although various embodiments have been described herein, manymodifications and variations to those embodiments may be implemented.For example, different types of end-effectors may be employed. Inaddition, combinations of the described embodiments may be used. Forexample, blade coatings may be formed of any combination of layermaterials and surface treatments described herein. Also, where materialsare disclosed for certain components, other materials may be used. Theforegoing description and following claims are intended to cover allsuch modification and variations.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

What is claimed is:
 1. An ultrasonic surgical instrument, comprising: awaveguide extending along a longitudinal axis; and an ultrasonic blade,comprising: a proximal end coupled to the waveguide; a distal endmovable relative to the longitudinal axis in accordance with ultrasonicvibrations applied to the waveguide; an outer surface; a first layeradhered to at least a portion of the outer surface; and a second layeroverlapping at least a portion of the first layer, wherein at least aportion of the second layer contacts the outer surface.
 2. Theultrasonic surgical instrument of claim 1, wherein the second layercomprises: a first portion comprising a first thickness; and a secondportion laterally offset from the first portion, wherein the secondportion comprises a second thickness, and wherein the second thicknessis less than the first thickness.
 3. The ultrasonic surgical instrumentof claim 2, wherein the first layer comprises a variable thickness. 4.The ultrasonic surgical instrument of claim 1, wherein the second layercomprises a variable thickness.
 5. The ultrasonic surgical instrument ofclaim 1, wherein at least a portion of the second layer is adhered tothe outer surface.
 6. The ultrasonic surgical instrument of claim 1,wherein the first layer comprises a first material, and wherein thesecond layer comprises a second material.
 7. The ultrasonic surgicalinstrument of claim 1, wherein the first layer is configured to enhanceadhesion of the second layer to the ultrasonic blade.
 8. The ultrasonicsurgical instrument of claim 1, wherein the ultrasonic blade is operablycoupled to a generator that is susceptible to a lockout condition atpower levels above a threshold power, and wherein the second layer isconfigured to reduce friction at an interface between a tissue and theultrasonic blade to avoid exceeding the threshold power draw by thegenerator to prevent the lockout condition.
 9. The ultrasonic surgicalinstrument of claim 1, further comprising a clamp arm movable between anunclamped position and a clamped position, wherein the clamp arm ispositioned opposite at least a portion of the second layer when theclamp arm is in the clamped position, and wherein the clamp arm isconfigured to clamp a tissue against the second layer when the clamp armis in the clamped position.
 10. An ultrasonic surgical instrument,comprising: a waveguide extending along a longitudinal axis; and anultrasonic blade, comprising: a proximal end coupled to the waveguide; adistal end movable relative to the longitudinal axis in accordance withultrasonic vibrations applied to the waveguide; an outer surfacecomprising a treatment region; and a plurality of layered coatings,comprising: a first coating, wherein at least a portion of the firstcoating contacts the outer surface; and a second coating overlapping atleast a portion of the first coating, wherein at least a portion of thesecond coating contacts the outer surface.
 11. The ultrasonic surgicalinstrument of claim 10, wherein the first coating comprising a firstmaterial, wherein the second coating comprising a second material, andwherein the second material is different than the first material.
 12. Anultrasonic surgical blade, comprising: a solid metal body comprising aproximal end configured to receive ultrasonic vibrations; an outersurface comprising a treatment region; and a plurality of coatings,comprising: a first coating; and a second coating at least partiallyoverlapping the first coating, wherein at least a portion of the secondcoating contacts the treatment region of the outer surface.
 13. Theultrasonic surgical blade of claim 12, wherein the first coatingcomprises: a first portion comprising a first thickness; and a secondportion laterally offset from the first portion, wherein the secondportion comprises a second thickness, and wherein the second thicknessis different than the first thickness.
 14. The ultrasonic surgical bladeof claim 12, wherein the first coating comprises a first material, andwherein the second coating comprises a second material.
 15. Theultrasonic surgical blade of claim 12, wherein the first coatingcomprises a variable thickness.
 16. The ultrasonic surgical blade ofclaim 12, wherein the second coating comprises a variable thickness. 17.The ultrasonic surgical blade of claim 12, wherein the first coating isconfigured to enhance adhesion of the second coating to the treatmentregion.
 18. The ultrasonic surgical blade of claim 12, wherein thetreatment region further comprises a surface treatment to enhanceadhesion of the plurality of coatings.
 19. The ultrasonic surgical bladeof claim 12, wherein the solid metal body is configured to operablycouple to a generator that is susceptible to a lockout condition atpower levels above a threshold power, and wherein the plurality ofcoatings are configured to reduce friction at an interface between atissue and the solid metal body to avoid exceeding the threshold powerdraw by the generator to prevent the lockout condition.